Mosley is determined to push through cost-cutting plans

FIA president Max Mosley proposed the radical idea to cut costs, with top teams spending more than �200m a year.

Teams have also been told they have eight days, starting from Thursday, to sign up for the 2008 championship or risk losing their place.

The move increases the pressure on the five road-car makers in F1 who are threatening to set up a rival series.

Renault, BMW, Honda, Mercedes-Benz and Toyota say they will break away if they are not granted more say in the running of the sport, a greater share of its revenues, and more transparency in its governance.

Discussions on technical regulations for 2008 will start after the entry deadline closes on 31 March and will be open only to those teams who have signed up.

We're not keen on the idea of freezing the whole engine Nick Fry Honda F1 boss

Any teams who miss the cut-off date can enter at a later date, but only if there are vacancies in a 12-team championship. Latecomers will have no say in shaping the rules.

An FIA statement said any rules that affected the design of the cars would be finalised by 30 June 2006, but that other rules could be "modified at any point up to the start of the 2008 season".

In a letter, Mosley said the 2008 sporting regulations, approved on Wednesday, had three aims:

• To reduce the cost of competing
• to improve the sporting spectacle
• to maintain, and where possible, improve current safety standards.

Other key changes for 2008 include:

• the imposition of a single tyre manufacturer for at least three years, and removal of the requirement for grooved tyres
• a restriction on testing to no more than 30,000km (18,600 miles) per team a year
• a ban on spare cars
• a weight penalty of 15kg if an engine is replaced before the end of its two-race cycle
• gearboxes to last for four races

The rubber-stamping of the new rules effectively means the rebel teams have to sign up to the 2008 championship and try to effect the changes they want from within - seriously weakening their negotiating position.

Renault came up with the idea of an engine freeze in F1

The body representing the rebel teams, the Grand Prix Manufacturers' Association, sent a letter to Mosley on Tuesday detailing a number of concerns it had over the new sporting regulations, including the engine freeze, and asking that the FIA delay on some of those issues.

Mosley replied on Wednesday saying that the World Council had taken account of the GPMA's letter but pressed ahead because it had been given no alternative proposals.

He added that "although the 2008 sporting regulations are now fixed, any element could be changed on proposal of a simple majority of the entered teams".

The FIA's announcement comes at a time when a rapprochement between it and the rebel teams had appeared increasingly likely.

Team bosses confident on future

The plan to freeze engine specifications for three years means manufacturers would submit an engine design to the FIA before 2008.

Honda are opposed to a severe limits on technology in F1

They would only be allowed to make approved modifications after that time.

The idea was initially put forward by Renault, one of the five members of the GPMA.

But some of the other members of the GPMA are against it.

For them, F1's appeal is in its high-technology - and they oppose Mosley's plans for restricting technical freedom in a number of ways.

"We're not keen on the idea of freezing the whole engine," Honda's F1 boss Nick Fry told Autosport.com. "It makes it very impractical for all the engine manufacturers."

Toyota F1 boss John Howett added: "Three years out is quite a long way to freeze an engine after a very limited period of running with it."